Drilling tool



June 26, 1962 R. o. BIGGS DRILLING Filed Aug. 18, 1969 F/fr EH." 5 m {a d 5 4% p 3 5 :I 4 in w INVENTOR. Hafiz-79f 0 5/4 43 United This invention relates to a drilling tool, and has as its primary object the provision of a tool which is adapted to encircle a well casing in an oil well, or the like for the purpose of drilling over or through cemented or stuck well casings so as to free the well casing in a well and allow it to -be pulled up and removed from the well.

An additional object of the invention is the provision of such -a device including a collar which is mounted on the well casing, and a plurality of radially disposed rotatable bits for the purpose of drilling either upwardly or downwardly through material adhering to the surface of the well casing to free the same.

An additional object of the invention is the provision of a device including means for rotating the individual drill bits from a common drill stem, which is actuated from the mouth of the well.

Still other objects reside in the combinations of elements, arrangements of parts, and features of construction, all as will be more fully pointed out hereinafter and disclosed in the accompanying drawing wherein there is shown a preferred embodiment of this inventive concept.

In the drawing:

FIGURE 1 is a side elevational view of one form of drilling tool embodying the instant invention shown as applied to a drill pipe.

FIGURE 2 is a sectional view taken substantially along the line 2-2 of FIG. 1 as viewed in the direction indicated by the arrows.

FIGURE 3 is a sectional view taken substantially along the line 33 of FIG. 1 as viewed in the direction indicated by the arrows.

FIGURE 4 is an enlarged fragmentary detail sectional view of a portion of the structure of FIG. 2; and

FIGURE 5 is an enlarged fragmentary detail sectional view of a portion of the structure of FIG. 3.

Similar reference characters refer to similar parts throughout the several views of the drawing.

Having reference now to the drawings in detail, there is generally indicated at a well casing, comprised of a plurality of sections 11, which are connected by conplings 12 at conventionally spaced intervals.

The drilling tool of the instant invention is generally indicated at 15, and comprises an upper collar member 16, and a similar lower collar member 17. The collar members 16 and 17 are adapted completely to encircle the pipe 10, and are so dimensioned as to pass over the couplings 12. The collars 16 and 17 are provided respectively with vertical bosses 18 and 19, the bosses being in alignment along one edge thereof, and adapted for the reception of a drill stem 20 which extends therethrough, being held in position by collars 21 and 22 at the upper and lower extremities of the bosses 18 and 19, respectively.

The lower end of drill stem 20 carries a drill bit 24 of conventional design in general, with the exception of the fact that the same is made of oval cross-sectional configuration so that it clears the side wall of the well casing 10 between the couplings 12, and due to its configuration, passes over the couplings 12 when turned to the proper position.

lntermediately of the upper and lower bosses 18 and 19 the drill stem 20 is provided with a plurality of vertically aligned and radially aligned rows of pins 25, which project outwardly from the surface of the stem, and serve as drive means for a rotatable sleeve 26, which is provided with a plurality of vertically and radially aligned rows of openings 27, which are counter sunk as at 28 (see FIG. 3)

atcnt 3,040,824 Patented June 26, 1962 5 ice r and which, when engaged by the rotating pins 25, serve to and serve rotatably to support a plurality of drill shafts 32.

The lower portion of each drill shaft 32 carries a rotatable sleeve or collar 33 which engages against the inner side of the collar 17 to avoid friction, and has at its lower-end a drill bit 34. The upper portion of each shaft 32 is provided with a collar 35, similar to the collars 33 and for the same purpose, and carries at its extremity a drill bit 36, in order that when the device is moved upwardly the drill bits 36 may effectively engage in any binding substance such as cement or the like above the collar.

It will thus be seen that as the sleeve 26 is rotated the sh ts 32 rotate therewith, and at the same time the drill bits 34 and 36 are rotated individually. This individual rotation is effected by the provision of a spur gear 37 on each of shafts 32-, which spur gears engage in openings 38, in a ring gear 39, which is carried interiorly of the collar 16 and fixed thereto. Obviously, as the sleeve 26 is rotated by the pins 25 the spur gears 37 will rotate the individual spindles 32 to rotate the drill bits 34 and 36, which in turn will effectively cut through any cement or other impediment holding the drill pipe in the well. The assembly 15 may be moved upwardly or downwardly as much as is necessary by means of the drill stem 20, which, it is to be noted, is rotated by any conventional means from the top of a well, until each individual impediment is removed and the drill pipe 10 is substantially clean, at which time, being free to float in the Well, it may be readily removed by conventional means.

It is to be noted that the drill bits 34 and 36 are also of oval cross sectional configuration to enable the same to pass over the couplings 12.

From the foregoing it will now be seen that there is herein provided an improved drilling implement which accomplishes all the objects of this invention, and others, including many advantages of great practical utility and commercial importance.

As many embodiments may be made of this inventive concept, and as many modifications may be made in the embodiment hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative, and not in a limiting sense.

I claim:

1. In a well drilling tool, a pair of spaced collars adapted to surround a well casing, aligned bearing-s carried by said collars exteriorly thereof, a rotatable drill stem extending through said bearings, a drill bit on the end of said stem below the lowermost of said collars, a sleeve rotatably mounted interiorly of said collars, means comprising a plurality of countersunk openings extending in aligned relation about the periphery of said sleeve and a plurality of pins carried by said drill stem engageable in said openings for rotating said sleeve by said drill stem, a plurality of vertical drill spindles rotatably mounted on said sleeve, drill bits on each end of each said drill spindles, and means comprising a spur gear carried by each drill spindle and a ring gear carried by the interior of one of said collars in engagement with said spur gears for rotating each drill spindle about its own was.

2. In a well drilling tool, a pair of collars adapted to 3 4 surround a Well casing in aligned and spaced relationship one of said pair of collars and said drill shafts for impartand having aligned bearing bosses thereon, a shaft exing rotation to the latter from the former. tending from the top of the Well journalled in said heating bosses, a sleeve rotatably mounted within said eollars References Cited in the file of this patent and adapted to surround the Well easing, gearing between 5 a the shaft and the sleeve for imparting rotation to the UNITED STATES PATENTS latter from the former, a plurality of drill shafts rota- 152L596 Casey 1925 tively mounted in said collars, drill bits carried by said 21197389 Tyler et a1 P 1940 drill shafts at their opposite ends, and gearing between 583,021 Brauer July 1954 

